CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Tong-liang Wu,Qian Sun,Guo-dong Fang,Pei-xin Cui,Cun Liu,Marcelo Eduardo Alves,Wen-xiu Qin,Dong-mei Zhou,Zhen-qing Shi,Yu-jun Wang
Natural organic matter (NOM) profoundly influences the metal(loid)s immobilization by iron (Fe) minerals, which, in turn, are the host phase for Sb that control its mobilization and bioavailability. However, the potential effect of the redox-active phenolic acids derived from NOM on this process has rarely been explored. Therefore, the adsorption of Sb(III) on goethite and Sb(III) oxidation in the presence of a common phenolic acid—gallic acid (GA)—was systematically investigated. The reaction mechanisms were unraveled by the combination of wet chemistry, electron paramagnetic resonance (EPR), X-ray photoelectron spectroscopy (XPS), and X-ray absorption fine structure (XAFS) spectroscopy. Our results showed the addition of GA significantly inhibited Sb adsorption on goethite as the pH increased. Except for the competitive adsorption by GA, the inhibition also resulted from the extensive Sb(III) oxidation in the suspension and the lower Sb(V) sorption capacity of goethite at higher pH. The alkaline condition facilitated the generation of reactive oxygen species (hydrogen peroxide) and quinone species (semiquinone radical (SQ − ) and oxidized GA), accounting for the significant Sb(III) oxidation in the solution and on the goethite surface. Besides, the edge-sharing inner-sphere complexes were formed between Sb and goethite regardless of the presence of GA. Our findings demonstrated the remarkable role of the phenolic groups in NOM on the adsorption of Sb(III) on goethite.
研究领域:
环境科学
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土壤化学
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产品关联
DOI
高影响因子
JOURNAL OF SOILS AND SEDIMENTS
·
2024
·Vol. 24
·期 6
·2309-2317
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IF 2.8
Mi Na,Yang Min,Wang Xiaohan,Sun Qian,He Jianzhou,Deng Shaopo,Fan Tingting
Purpose The application of silicon could effectively alleviate Cd contamination in the soil. However, the interaction between silicon and Cd in soils is not well understood. Our research aims to investigate the mechanism of the impact of silicate on the sorption of Cd on metal oxides in soils. Materials and methods Sodium silicate and Cd(II) co-sorption on γ-Al 2 O 3 and goethite at pH 5.5 and 7.5 was studied using a combination of batch sorption experiments, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Results and discussion Silicate enhanced the sorption of Cd(II) onto γ-Al 2 O 3 at pH 5.5 and 7.5. However, the sorption of Cd(II) on goethite at pH 5.5 and 7.5 was only promoted when the silicate concentration reached 1 mmol L −1 . Cadmium(II) enhanced silicate sorption on γ-Al 2 O 3 at pH 5.5 and on goethite at pH 7.5, while it decreased silicate sorption on γ-Al 2 O 3 at pH 7.5 and had no significant effect on goethite at pH 5.5. At pH 5.5, Cd(II) reacted with silicate to generate Cd 2 SiO 4 , and Cd-Si-Al ternary complexes were formed on γ-Al 2 O 3 . At pH 7.5, silicate promoted the formation of Cd(OH) 2 on γ-Al 2 O 3 , which ultimately transformed into CdCO 3 . When silicate concentration reached 1 mmol L −1 , more silicate complexes were formed through the Fe-O-Si bound on goethite at both pH 5.5 and 7.5 to promote the adsorption of Cd(II) owing to its electronegative functional group on the surface of the complex. Conclusions The type of clay minerals, pH, and the presence of silicate all significantly affected Cd sorption. Furthermore, the sorption mechanism of Cd on γ-Al 2 O 3 and goethite in the presence of silicate has been elucidated. The above findings improve our understanding of the mechanism for immobilizing Cd in soils using silicon-containing materials.
研究领域:
土壤科学
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环境化学
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DOI
高影响因子
Nanomaterials
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2019
·Vol. 9
·期 8
·1143
·
IF 4.034
Hai-Tao Ren,Jing Han,Ting-Ting Li,Qi Lin,Jia-Horng Lin,Ching-Wen Lou
The fate of arsenic in the water environment is of great concern. Here, the influences of oxalic acid and UV light illumination on the dissolution of naked ferrihydrite (Fhy), Fhy loaded with As(V) [Fhy*-As(V)], as well as the fate of As(V) at pH 3.0 were studied. With the assistance of oxalic acid, complexes of Fe(III)-oxalic acid produced on Fhy/Fhy*-As(V) were reduced to Fe(II)-oxalic acid by photo-induced electrons under UV light irradiation. UV light has nearly no impact on the release of As(V) in the system of Fhy*-As(V) without the assistance of oxalic acid. Nevertheless, in the existence of oxalic acid, UV light illumination resulted in the contents of liberated As(V) decreased by 775–1300% compared to that without light. Considering the coexistence of As(V), oxalic acid as well as iron oxides in aquatic environments, the present study revealed that UV illumination could enhance the retention of As(V) on Fhy in the acidic water environment containing oxalic acid.Keywords:ferrihydrite;As(V);photodissolution;oxalic acid;fate
研究领域:
环境科学
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化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2021
·
IF 3.196
Yajie Wang,Xianhe Gong,Xin Dong,Yunjie Wu
In this work, arsenite (As(III)) removal in a goethite/oxalate suspension under UVA-irradiation (λ max = 365 nm) was explored under different conditions (initial pH, oxalate concentration, goethite dosage, and phosphate). SEM, EDS, FTIR, XRD and XPS were used to investigate the morphology, composition, functional groups, structure, and surface properites of goethite. The greatest efficiency of As(III) removal was 95.52% at pH 3.0, 100.0 µg·L –1 As(III), 0.05 g·L –1 goethite, and 0.5 mmol·L –1 oxalate. The removal of As(III) in the goethite/oxalate system was strongly pH-dependent. An increase in pH was accompanied by a reduction in photo-oxidation efficiency and an increase in adsorption efficiency. Addition of appropriate amounts of oxalate can enhance As(III) removal at pH 3.0 by promoting the photo-dissolution of iron oxide. However, the addition of oxalate was detrimental to As(III) removal at pH 7.0 due to its competition for photo-generated hole ( h vb + ) as well as adsorption sites. Increasing dosage from 0.0 to 0.5 g·L –1 accelerated As(III) removal at both pH 3.0 and pH 7.0. ESR, radical-scavenging, and N 2 -purging experiments showed that As(III) removal was mainly achieved by photo-oxidation at pH 3.0 and HO · appeared to be the primary oxidant for the As(III) oxidation, which was strongly dependent on HO 2 · /O 2 ·– . However, adsorption served as a major pathway and photo-oxidation played a minor role at pH 7.0. As(III) photo-oxidation was predominantly attributed to the direct reaction between As(III) and h vb + under neutral conditions. In addition, O 2 played an important role in As(III) photo-oxidation under acidic and neutral conditions. Moreover, goethite remained morphologically intact and demonstrated good reusability up to five regeneration cycles. These findings show that As(III) can be effectively removed from water containing iron oxides and carboxylic acid, which is important for the remediation of arsenic-contaminated waterbodies and wastewaters.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2023
·Vol. 31
·期 4
·6411-6424
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IF 5.8
Li Yujia,Bi Erping
The interactions between organic pollutants and iron minerals play an important role in their environmental fate. In this study, the effects of low-molecular-weight organic acids (LMWOAs) on the adsorption and degradation of tetracycline (TC) on goethite were investigated. Tartaric acid (TA) was taken as the representative of LMWOAs to study the influencing mechanism through batch experiments and microscale characterization. In addition, the properties of TC-TA clusters under different pHs were determined by density functional theory (DFT) calculations. The results showed that all five LMWOAs inhibited TC adsorption and degradation. The preferential adsorption of TA on goethite changed TC adsorption from inner spherical to outer spherical complexation and mainly inhibited TC adsorption and degradation of the singly coordinated hydroxyl group. TC degradation rate decreased from 0.0287 to 0 h −1 in the first stage. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results showed that TA could influence the interactions of amide groups, C = O on the A-ring, and dimethylamino group of TC with goethite, and the formation of ≡Fe(II) was inhibited. In addition to competing for the effective sites, the effects of complexation between TA and TC in solution should be considered. According to DFT calculations, hydrogen bonds could be formed between the carboxyl group of TA and the H atom of TC at different pH. These findings can provide evidence for estimating the contribution of adsorption and degradation to TC removal by iron oxides with the coexistence of LMWOAs in a soil–water environment. Graphical Abstract
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
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2024
·
IF 1
Shifeng Li,Feng Lu,Shuhua Yao,Shuyan Zang
The mesoporous goethite synthesized by the hydrothermal method was employed to remove selenate (Se(VI)) and selenite (Se(IV)) from wastewater. The adsorption data of kinetics and isotherms were determined and fitted with different models, and the potential adsorption mechanism was discussed according to X-ray photoelectron spectroscopy (XPS) analysis. The maximum adsorption capacities of Se(IV) and Se(VI) on the mesoporous goethite are 71.07 and 21.07 mg/g at 25°C, respectively, which are about two orders of magnitude higher than the natural goethite. The XPS results revealed that the Se(IV) was adsorbed on the surface of the mesoporous by the formation of the inner-sphere complex, but the outer-sphere complexes are formed with Se(IV). The meso-porous goethite is expected to be a potential adsorbent for Se removal from industrial selenium- containing wastewater on a large scale for its properties of easy-preparation and less cost compared with classic nanomaterials.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
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2023
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IF 8.8
Liang Tao,Wenjie Chen,Yuxin Liu,Feng Yang,Dong Liu,Junfen Liang,Saihong Liu,Hui Li
Soil acidification in southern China increases the environmental risk posed by heavy metals, especially cadmium (Cd), and has been accelerated by anthropic activities . Long-term fertilizer use increases the quantity of phosphate (P) in soils, which affects the biogeochemistry of heavy metals in soil environments. In this study, various analytical methods were used to investigate the critical mechanisms controlling P(V)–Cd(II) interactions with goethite (α-FeOOH, a typical iron oxide widely distributed in red soil areas) with added P(V)/Cd(II) in different molar ratios (to simulate the annual P fertilizer surplus). After excluding pH interference by using organic buffers, Cd(II) adsorption processes on α-FeOOH were found to be enhanced by the presence of P(V), whereas the Cd(II) adsorption type changed from single inner-sphere complexation to both inner- and outer-sphere complexation. The results of a zeta potential analysis, X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) showed different dominant mechanisms underlying the promotion of Cd(II) adsorption by P(V) at different P(V)/Cd(II) molar ratios. Electrostatic adsorption and the formation of ternary complexes were proven to be the critical mechanisms controlling the reactivity of Cd(II), where coprecipitation occurs at high P(V)/Cd(II) molar ratios and considerably enhances the fixation of Cd(II) and P(V). The mechanism for Cd(II) and P(V) coadsorption onto α-FeOOH under stable pH conditions was found to include both competitive and synergistic effects, and the results in this study show that more attention should be given to the impact of anthropic activities on the reactivity of heavy metals in the soil environment, especially farmland.
研究领域:
环境科学
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土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WATER RESEARCH
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2024
·
IF 11.4
Hongmei Tang,Meiqing Chen,Pingxiao Wu,Yihao Li,Tianming Wang,Jiayan Wu,Leiye Sun,Zhongbo Shang
Schwertmannite (Sch) is considered as an effective remover of Chromium (Cr) due to its strong affinity for toxic Cr species. Since the instability of Sch, the environmental fate of Cr deserves attention during the transformation of Sch into a more stable crystalline phase. The ubiquitous manganese(II) (Mn(II)) probably affects the transformation of Sch and thus the environmental fate of Cr. Therefore, this study investigated the impact of Mn(II) on the transformation of Cr-absorbed Sch (Cr-Sch) and the associated behavior of SO 4 2− and Cr. We revealed that the transformation products of Cr-Sch at pH 3.0 and 7.0 were goethite and Sch, respectively. The presence of Mn(II) weakened the crystallinity of the transformation products, and the trend was positively correlated with the concentration of Mn(II). However, Mn(II) changed the transformation products of Cr-Sch from hematite to goethite at pH 10.0. Mn(II) replaced Fe(III) in the mineral structures or formed Mn-O complexes with surface hydroxyl groups (-OH), thereby affecting the transformation pathways of Sch. The presence of Mn(II) enhanced the immobilization of Cr on minerals at pH 3.0 and 7.0. Sch is likely to provide an channel for electron transfer between Mn(II) and Cr(VI), which promotes the reduction of Cr(VI). Meanwhile, Mn(Ⅱ) induced more -OH production on the surface of secondary minerals, which played an important role in increasing the Cr fixation. In addition, part of the Mn(Ⅱ) was oxidized to Mn(Ⅲ)/Mn(Ⅳ) at pH 3.0 and pH 7.0. This study helps to predict the role of Mn(II) in the transformations of Cr-Sch in environments and design remediation strategies for Cr contamination.
研究领域:
环境科学
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矿物学
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DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2019
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IF 6.361
Jie Cao,Jin Huang,Huaping Dong,Jianfa Li,Jianxin Shou,Yimin Li
Surfactants are easily accumulated in groundwater, sediment, and aquifers, due to their excessive use in household, industrial, and agricultural processes. These residual surfactants are expected to influence the transformation and fate of organic contaminants by Fe(II) sorbed on iron oxides in anaerobic environments. Here, we investigated the effects of various surfactants including nonionic TX-100, anionic SDBS and bio-surfactant saponin on the removal of nitrobenzene (NB) by Fe(II) sorbed on goethite (goethite/Fe(II)) through batch experiments. We also elucidated the mechanism behind the effects by XPS, XRD , and determination of the amounts of sorbed Fe(II) on goethite. The results showed that the presence of TX-100 improved NB removal from 77.2% in the absence of surfactant, to 93.8% within 6 h, and improved the removal rate by about 1.3 times. In contrast, the presence of SDBS decreased the removal efficiency to 45.5%, and the presence of saponin nearly inhibited the removal of NB completely. The removed NB was finally nearly reduced to aniline in the absence or presence of surfactants, except in the case of saponin. The amounts of sorbed Fe(II) listed in the sequence as goethite/Fe(II)+TX-100 > goethite/Fe(II) > goethite/Fe(II)+SDBS > goethite/Fe(II)+saponin, and this order negatively correlated with that in the redox potential of these systems. These results confirmed that the presence of surfactants influenced the sorption of Fe(II) on goethite and changed the reactivity of goethite/Fe(II) for NB removal. This finding will promote a clear understanding of the impact of coexisting surfactants on the transformation and fate of organic contaminants in real anaerobic environments.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Sciences
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2021
·
IF 5.565
Ji Li,Chenlu Shi,Wenbin Zeng,Yaru Wang,Zebin Hong,Yibing Ma,Liping Fang
Electron shuttles such cysteine play an important role in Fe cycle and its availability in soils, while the roles of pH and organic ligands in this process are poorly understood. Herein, the reductive dissolution process of goethite by cysteine were explored in the presence of organic ligands. Our results showed that cysteine exhibited a strong reactivity towards goethite – a typical iron minerals in paddy soils with a rate constant ranging from 0.01 to 0.1 hr −1 . However, a large portion of Fe(II) appeared to be “structural species” retained on the surface. The decline of pH was favorable to generate more Fe(II) ions and enhancing tendency of Fe(II) release to solution. The decline of generation of Fe(II) by increasing pH was likely to be caused by a lower redox potential and the nature of cysteine pH-dependent adsorption towards goethite. Interestingly, the co-existence of oxalate and citrate ligands also enhanced the rate constant of Fe(II) release from 0.09 to 0.15 hr −1 ; nevertheless, they negligibly affected the overall generation of Fe(II) in opposition to the pH effect. Further spectroscopic evidence demonstrated that two molecules of cysteine could form disulfide bonds (S-S) to generate cystine through oxidative dehydration, and subsequently, inducing electron transfer from cysteine to the structural Fe(III) on goethite; meanwhile, those organic ligands act as Fe(II) “strippers”. The findings of this work provide new insights into the understanding of the different roles of pH and organic ligands on the generation and release of Fe induced by electron shuttles in soils.
研究领域:
土壤科学
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环境化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Coatings
·
2023
·Vol. 13
·期 6
·1097
·
IF 3.4
Xiaoqing Meng,Lin Wang,Ying Yang,Yuqi Song,Cansheng Yuan
Sulfamethoxazole (SMX) contamination in large quantities of wastewater can cause potential environmental problems. Due to difficulty in degrading SMX by natural processes, it is necessary to develop a novel technology to solve this problem. Advanced oxidation processes (AOPs) have been identified as methods with a high potential to treat recalcitrant organic pollutants. The nanoscale schwertmannite (nano-SWT) was prepared with an indoor-temperature synthesis method facilitated by polyvinylpyrrolidone (PVP). In this study, we performed a reaction of the nano-SWT materials with Fenton-like catalysts for SMX degradation in hydrogen peroxide (H2O2) media. The findings showed that the nano-SWT prepared by addition of 0.1 g·L−1PVP (nano-SWT-n,n= 0.1) could degrade 92.5% of the SMX within 90 min at indoor temperature, which was due to the nano-SWT providing abundant reaction sites at the solid/solution interfaces. Additionally, SMX could be highly mineralized with 75% TOC removal and H2O2was efficiently utilized during the nano-SWT/H2O2process. In addition, after six cycles of Fenton-like degradation, the nano-SWT remained stable and reusable as a Fenton-like catalyst for SMX degradation. The nano-SWT performed well as a catalyst for SMX degradation. Additionally, this work provides a feasible environmental purification approach for the efficient degradation of SMX through the use of nanoscale schwertmannite as a catalyst in heterogeneous Fenton-like systems.Keywords:Fenton-like;sulfamethoxazole;nanoscale schwertmannite;degradation
研究领域:
环境科学
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化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 17
·4172
·
IF 3.1
Wei Ding,Shenxu Bao,Yimin Zhang,Bo Chen,Zhanhao Wang
Antimony (Sb) migration in soil and water systems is predominantly governed by its adsorption onto ferrihydrite (FH), a process strongly influenced by natural organic matter. This study investigates the adsorption behavior, stability, and mechanism of FH and FH–humic acid (FH-HA) complexes on Sb(V), along with the fate of adsorbed Sb(V) during FH aging. Batch adsorption experiments reveal that initial pH and concentration significantly influence Sb(V) sorption. Lower pH levels decrease adsorption, while higher concentrations enhance it. Sb(V) adsorption increases with prolonged contact time, with FH exhibiting a higher adsorption capacity than FH-HA complexes. Incorporating HA onto FH surfaces reduces reactive adsorption sites, decreasing Sb(V) adsorption. Adsorbed FH-HA complexes exhibit a higher specific surface area than co-precipitated FH-HA, demonstrating stronger Sb(V) adsorption capacity under various conditions. X-ray photoelectron spectroscopy (XPS) confirms that Sb(V) adsorption primarily occurs through ligand exchange, forming Fe-O-Sb complexes. HA inhibits the migration of Sb(V), thereby enhancing its retention within the FH and FH-HA complexes. During FH transformation, a portion of Sb(V) may replace Fe(III) within converted iron minerals. However, the combination of relatively high adsorption capacity and significantly lower desorption rates makes adsorbed FH-HA complexes promising candidates for sustained Sb adsorption over extended periods. These findings enhance our understanding of Sb(V) behavior and offer insights for effective remediation strategies in complex environmental systems.
研究领域:
环境科学
·
土壤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）